Here's the warranty. There's no valid reason for any of us to use a non-Samsung tool (Odin) to replace our device's s/w with s/w from another region it's not intended to run. There are tons of terms below that could be applied to flashing non-approved s/w even if it's official in another region. I'm not saying you will have a problem, I'm saying you could. And the only one you have to convince you're entitled to warranty support should you need it is the Samsung rep you're talking to.
Warranty periods and warranty services are intended as a guide only and variations may occur. The warranty period applies from the date of purchase by the first customer and is transferable only between end-users. The warranty covers manufacturing defects only. Please note that this does not include consumables items such as batteries, bulbs, and ink cartridges unless listed above under 'general information'. The liability of Samsung Electronics (or its appointed maintenance agent) is limited to the cost of repair and/or replacement of the product under warranty. The warranty is invalidated if the defect is caused (howsoever) by misuse, neglect, and tampering or incorrect adjustment. It is invalidated if unauthorized persons carry out any alterations and/or repairs. Also, the warranty is invalidated in the following cases:
-For the repair of a domestic product used in a commercial environment.
-For repair due to incorrect installation in your home
-For repair to any product where the serial number has been removed
damage that is attached to or used in connection with the product. Samsung Electronics (UK) Ltd support a product purchased in Europe if it has an EU Bloc Warranty. This warranty is present where the top of the product warranty card clearly states 'European Bloc'. If the product is purchased in another part of the globe then Samsung may attempt a repair. Samsung Electronics (UK) Ltd cannot guarantee the outcome.
As a UK user, there is EVERY reason to run a different firmware, currently there is no official samsung uk file that enables the use of 4G, the only way to enable 4g is to use a different firmware from a different country, as it is in the uk I believe it's only the 16 GB wifi p600 available within the uk, maybe there is a 32GB version but again wifi only. For me it was far more sense to buy the 605 model which also has the better chipset, and then set about flashing a different firmware. Again my kids will be using the tablet so it is important it has multiuser support, again something not available with the uk firmware. This whole, you'll invalidate your warranty thing is a bit OTT, I know for one if there was a problem i might accidently drop the tablet on my tiled floor, my house insurance would cover it anyways!!! I got my 605 32GB for £353 delivered from an amazon seller, it's from HKong, it took 8 days to arrive!!! Couldn't be happier. I'm quite happy to read up then root the device, I'm not planning on selling it on it'll prob stay in my family til it dies, I appreciate that not everyone is confident with technology or maybe can afford to 'take a risk' as it were, but people basically scare-mongering is not good either. I learnt to overclock by reading and trying out, you risk a little to gain a little, from what I've read so far, there isn't a huge risk rooting at all, unless you have a powercut mid flash!! If you aren't planning on selling on, why worry about KNOX?